Elastic fabric and process of preparation

ABSTRACT

The disclosure provides a woven fabric, wherein all warp and weft yarns may be elastic. One or more of the weft and warp yarns may have a stretchable core comprising a first elastic fiber and a second fiber that may be less elastic than said first fiber. In embodiments, the elasticity of the fabric in the warp direction may be at least 25% and the elasticity of the fabric in the weft direction (E weft ) may be at least 25%. In embodiments, the elasticity of the fabric in the weft direction (E weft ) may be at least 30%. In embodiments, the elasticity of the fabric in the weft direction (E weft ) may be at least 40%.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to European Patent Application No. EP15161213, filed with the European Patent Office on Mar. 26, 2015, which is hereby incorporated by reference in its entirety.

Suitable elastic core spun yarns may be those disclosed in WO2012/062480, which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present disclosure teaches woven fabrics with stretch in the warp and weft directions and the method of its manufacture. It specifically relates to stretchable fabrics including a core spun yarn system and a method for the preparation thereof.

BACKGROUND OF THE INVENTION

Elastic woven fabrics have been produced for many years. In order to produce elastic fabrics, elastic yarns are used. In these kinds of fabrics, elastic yarns provide both aesthetic, and elasticity functions. The most common stretchable fabrics are weft-stretch fabrics. Weft-stretch fabrics have non-elastic warp yarns and elastic weft yarns. In these fabrics different kinds of elastic weft yarns such as, but not limited to corespun elasthane yarns, twisted elasthane yarns, etc. are used. However, weft-stretch fabrics are not stretchable along the warp direction. Such fabrics are usually comfortable, but their comfort level is not enough during long usage times, as they do not follow the movements of the body.

In order to solve this problem, several alternative types of fabrics have been developed, for example warp-stretch fabrics, and the so called “bi-stretch” fabrics, i.e. fabrics that can be stretched in both the weft and warp directions. This bidirectional stretchability, i.e. ability to be elongated, is obtained by including elastic yarns in both the warp and weft directions.

However, these kinds of fabrics present drawbacks.

Warp-stretch fabrics, for example, when comprising bare elastomeric ends, can present grin-through of the elastomer, i.e. the exposure, in a fabric, of bare elastomeric filaments to view. Grin-through can be observed as an undesirable glitter-like effect on the surface of the fabric. Therefore, some ways to control elasticity in bi-stretch fabrics have been devised.

U.S. Pat. No. 6,659,139 describes a way to reduce grin-through of bare elastomer fibers in the warp direction of twill fabric. The fabric disclosed in U.S. Pat. No. 6,659,139 can also have bidirectional stretch (warp and weft), but the percentage values of stretchability are poor.

Bi-stretch fabrics known in the art also have several problems, such as the growth of the fabric and little recovery after stretching.

WO2013/148659 discloses a woven fabric comprising a corespun elastic base yarn and a separate control yarn, to avoid overstretching. The control yarn is hidden inside the fabric by the adjacent elastic corespun base yarns.

A stretch fabric with a separated elastic yarn system is disclosed in U.S. Pat. No. 7,762,287, wherein a rigid yarn is used to form the main body of a fabric. Elastic composite yarns are hidden inside of the fabrics and provide for stretch and recovery. However, the fabric disclosed in U.S. Pat. No. 7,762,287 has reduced stretchability in the warp and/or weft direction.

US 2012/0244771 discloses elastic composite yarns having a stretchable core and a sheath of spun staple fibers; the core is made of an elastic filament and an inelastic filament that is loosely wound around the elastic filament to control the stretching. The above disclosed solution provides bi-stretch fabrics that have acceptable recovery characteristics but are provided with too low elasticity (i.e. stretch), namely about 10-12% in the warp direction and 17-20% in the weft direction.

WO20008/130563 discloses elastic yarns having a core made of an inelastic fiber loosely wound around an elastic fiber.

WO 2012/062480, in the name of the present applicant Sanko Tekstil, discloses elastic composite yarns having elastic stretchable core and a sheath of inelastic staple fibers; the core is made of an elastic filament and a less elastic filament attached together by coextrusion, intermingling, or twisting. The less elastic filament controls the stretch and provides recovery so as to move as a single fiber that has high elasticity and very good recovery properties.

Another problem is the poor behavior of highly elastic bi-stretch fabrics: after few stretch and return cycles, the known fabrics are not able to retain their original aspect. The fabrics lose their original hand and appearance, and show curling, creasing, and torqueing to such a degree that the garments made with said fabrics have to be discarded after a short time.

A problem of the known bi-stretch fabrics, for example denim fabrics, is that it is difficult to obtain a fabric with an appropriate balance of physical characteristics, suitable for garments able to combine desirable visual and tactile aesthetics, with good performance in stretchability, recovery (i.e. limited growth of the fabric after having been elongated or stretched), and comfort.

For example, fabrics with a high amount of elastic yarns can have the problem of loss of aesthetic qualities, especially because of growth; on the contrary, fabrics with low values of elasticity can be uncomfortable in daily life. Additionally, prolonged usage of stretch fabrics can cause a loss in recovery power of the fabric, thus causing the growth of the fabric. Another problem of the known fabrics, for example denim fabrics, is the poor body holding, i.e. body shaping power.

The above problems of recovery power, comfort in use and holding/shaping power of the fabric are particularly present in the final garments that are styled in the so-called skinny or super-skinny models; i.e. models that require a total or almost total adherence of the garment to the body of the user.

In view of the above mentioned problems, there is a need for new fabrics able to combine high elasticity in multiple directions and good aesthetics; for example, there is a need in the market for new fabrics having an improved holding power and recovery, reduced growth, and are combined with good visual and tactile aesthetics.

In particular, there is a need for new bi-stretch fabrics, for example denim fabrics, with an improved holding/shaping power, having an improved recovery and reduced growth.

More specifically, there is a need of new bi-stretch fabrics, such as denim fabrics, with an improved body holding power and fabrics that can follow any body movement.

BRIEF SUMMARY OF THE INVENTION

As used herein, “E_(weft)” and “E_(warp)” may respectively refer to the percentage of stretch in the weft and in the warp directions of the fabric, measured according to ASTM D3107 MODIFIED (Stretch) after 3 home washes.

In embodiments, the disclosure may provide bi-stretch woven fabrics with improved holding power. In embodiments, the fabric may provide, to garments made with the fabric, a great freedom of movement, thus avoiding the feeling of tightness and discomfort by a user.

In embodiments, the disclosure may provide a bi-stretch woven fabric that combines good performance, such as improved body holding/shaping power, improved recovery, and reduced growth with good aesthetics.

In embodiments, the disclosure may provide a process for producing a bi-stretch woven fabric, as mentioned above.

In embodiments, the disclosure may provide a clothing article comprising a bi-stretch woven fabric, as mentioned above.

In embodiments, these aims may be achieved by a woven fabric according to claim 1 that may be produced by means of a process according to claim 26 and that may be used to provide a clothing article according to claim 25.

In embodiments, the disclosure may provide a woven fabric having elastic warp yarns and elastic weft yarns, said yarns having a stretchable core and an inelastic fiber sheath that covers said core. In embodiments, all weft and warp yarns may have a stretchable core comprising a first elastic fiber and a second fiber that is less elastic than the first fiber. In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be at least 25% (measured according to ASTM D3107-Stretch, after 3 home washes) and the elasticity of the fabric in the weft direction (E_(weft)) may be at least 25%. In embodiments, the elasticity may be at least 30%. In embodiments, the elasticity may be 40%. In embodiments, the elasticity may be more than 40% (ASTM D3107; stretch, after 3 home washes).

In embodiments, in a woven fabric, a first fiber and second fiber may be connected together by intermingling, twisting, and/or coextrusion in order to control elongation of the first fiber.

In a particular embodiment, said woven fabric may have elasticity in the weft direction that may be greater than the elasticity in the warp direction. In embodiments, said woven fabric may have elasticity in the warp direction that may be greater than the elasticity in the weft direction.

In embodiments, the elasticity of the fabric in the warp direction may be at least 25% (measured according to ASTM D3107-Stretch, after 3 home washes) and the elasticity of the fabric in the weft direction (E_(weft)) may be at least 25% and may be the same or higher than the elasticity in warp direction (E_(warp)). In embodiments, the elasticity may be at least 30% and may be the same or higher than the elasticity in warp direction (E_(warp)). In embodiments, the elasticity may be at least 40% (ASTM D3107-stretch, after 3 home washes) and may be the same or higher than the elasticity in warp direction (E_(warp)). In other words, the fabric may stretch at least 25% in the warp direction and at least 25% in the weft direction or may stretch at least 30% in the warp direction and at least 30% in the weft direction or may stretch at least 40% in the warp direction and at least 40% in the weft direction when measuring according to ASTM D3107 (modified stretch after 3 home washes) as mentioned above.

In embodiments, the fabric may undergo finishing steps but may not undergo a heat setting treatment for elastic yarns. Heat treatment, i.e. heat setting of a fabric is a well-known step of traditional processes of fabric preparation, used e.g. to give dimensional stability to the elastic fabric after weaving by heating the fabric to a setting temperature for the elastomers of the elastic core of the yarns. E.g., the temperature for heat setting of Lycra (a registered trademark of Invista) is about 180° C. In embodiments, heat treatment at lower temperatures, such as sanforization at about 110° C., may be carried out in the a process of the disclosure. In embodiments, elasticity in the warp direction (E_(warp)) may be in the range of 25% to 90%. In embodiments, elasticity in the warp direction (E_(warp)) may be in the range of 30% to 90%. In embodiments, elasticity in the warp direction (E_(warp)) may be in the range of 30% to 60% measured according to (ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, elasticity in the weft direction (E_(weft)) may be in the range of 30% to 150%. In embodiments, elasticity in the weft direction (E_(weft)) may be in the range of 30% to 140%. In embodiments, elasticity in the weft direction (E_(weft)) may be in the range of 35% to 125%. In embodiments, elasticity in the weft direction (E_(weft)) may be 40% to 125%. The stretch may be measured according to ASTM D1037 MODIFIED (Stretch) after 3 home washes.

In an exemplary embodiment, the ratio E_(weft)/E_(warp) may be in the range of 1.4/1.0 to 3.0/1.0. In embodiments, the ratio E_(weft)/E_(warp) may be in the range of 1.8/1.0 to 3.0/1.0.

In another exemplary embodiment, the ratio E_(weft)/E_(warp) may be in the range of 0.4/1.0 to 4.0/1.0.

In embodiments, the first fiber may be a fiber that may stretch at least 400% of its initial length at its breaking point. In embodiments, the second fiber may be a fiber with an elongation that may be at least 20% of its initial length but less than the elongation of the first fiber, according to ASTM D3107. In embodiments, the first fiber and the second fiber may be connected together as disclosed in mentioned applications such as in pages 9 and 10 of WO2012/062480. In embodiments, the first and second fibers may be intermingled. In embodiments, the number of connecting points between the first and second fibers may be within the range of 50 to 200 points per meter. In another embodiment, the first and second fibers may be connected by twisting. In embodiments, the number of twists per meter of the first and second fibers may be in the range of 200 to 600 twists per meter. In embodiments, the number of twists per meter of the first and second fibers may be in the range of 300 to 600 twists per meter.

In embodiments, the core of the yarns may be intermingled or twisted as per the discussion above, wherein the fabric is not a heat-set fabric, i.e. the fabric has not undergone a thermal treatment, as is generally done to set elasticity of the elastomeric fibers.

It had been found in specific embodiments that an elastic woven fabric may have an excellent elastic behavior. In particular embodiments, it may be possible to use highly elastic yarns to obtain highly elastic fabric both warp and weft-wise that was not possible with traditional fabrics and processes. In embodiments, the processes disclosed may result in a fabric that may stretch up to 150% (ASTM D1037 MODIFIED (Stretch) after 3 home washes), or, in embodiments, a fabric may stretch over 150% weftwise and may return to its original shape after such a stretch. The fabric after the stretch may be visually identical to the fabric before the stretch.

Other fabrics not disclosed may not be able to obtain the stretchability of the fabrics in the disclosure. The other fabrics may suffer visual damages in the form of undulations or torqueing.

In embodiments, an elastic woven fabric having specific values of elasticity in the warp direction and specific values of elasticity in the weft direction may comprise an improved holding power (or shaping power). In embodiments, when the values of E_(weft) and E_(warp) are combined in a specific ratio, the elastic woven fabric may comprise an improved holding power (or shaping power). In embodiments, the disclosure may provide an elastic woven fabric comprising elastic yarns of the core spun type both warpwise and weftwise so that all yarns of the fabric may be elastic yarns. In an exemplary embodiment, the fabric may have specific values of elasticity and a specific ratio between E_(warp) and E_(weft). In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be at least 25% and the elasticity of the fabric in the weft direction (E_(weft)) may be equal to or higher than E_(warp). In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be at least 25% and the elasticity of the fabric in the warp direction (E_(warp)) may be equal to or greater than the elasticity of the fabric in the weft direction (E_(weft)). In embodiments, E_(weft) may be about twice the value of E_(warp), which may provide an improved body holding power, improved movement skills, and a reduced growth of the fabric and of garments comprising the fabric.

Embodiments may provide a process for preparing said elastic woven fabric. The process may comprise steps including providing corespun warp yarns and weft yarns each having a stretchable core. In embodiments, an inelastic fiber sheath may cover the core. In embodiments, the stretchable core may comprise a first elastic fiber and a second fiber that may be less elastic than the first fiber. The process may further include weaving the warp and weft yarns to provide a fabric wherein all warp and all weft yarns may be corespun yarns. The process may further include finishing the fabric in order to provide a fabric that may have elasticity in the warp direction (E_(warp)) that may be at least 25% and an elasticity in the weft direction (E_(weft)) that may be at least 25% (measured according to ASTM D3107-Stretch, after 3 home washes). In embodiments, the process may further include finishing the fabric in order to provide a fabric that may have elasticity in the warp direction (E_(warp)) that may be at least 30% and an elasticity in the weft direction (E_(weft)) that may be at least 30% (measured according to ASTM D3107-Stretch, after 3 home washes). In embodiments, the process may further include finishing the fabric in order to provide a fabric that may have elasticity in the warp direction (E_(warp)) that may be at least 40% and an elasticity in the weft direction (E_(weft)) that may be at least 40% (measured according to ASTM D3107-Stretch, after 3 home washes).

In embodiments of the process, the first fiber and the second fiber may be connected together by intermingling, coextrusion, and/or twisting in order to control the elongation of the first fiber.

In embodiments, elasticity in the weft direction (E_(weft)) may be greater than the elasticity in warp direction (E_(warp)). In embodiments, elasticity in the warp direction (E_(warp)) may be greater than the elasticity in the weft direction (E_(weft)).

In embodiments, a process may comprise steps including providing corespun warp yarns and weft yarns having a stretchable core and an inelastic fiber sheath that covers the core. In embodiments, the stretchable core may comprise a first elastic fiber and a second fiber that may be less elastic than the first fiber. In embodiments, the first fiber and second fiber may be connected together by intermingling, coextrusing, and/or twisting in order to control elongation of the first fiber. The process may further include weaving the warp and weft yarns may provide a fabric wherein all warp and all weft yarns may be corespun yarns. The process may further include finishing the fabric may provide a fabric that may have an elasticity in the warp direction (E_(warp)) that may be at least 25% and an elasticity in weft direction (E_(weft)) that may be at least 25% (measured according to ASTM D3107-Stretch, after 3 home washes). In embodiments, finishing the fabric may provide a fabric that may have an elasticity in the warp direction (E_(warp)) that may be at least 30% and an elasticity in weft direction (E_(weft)) that may be at least 30% (measured according to ASTM D3107−Stretch, after 3 home washes). In embodiments, finishing the fabric may provide a fabric that may have an elasticity in the warp direction (E_(warp)) that may be at least 40% and an elasticity in weft direction (E_(weft)) that may be at least 40% (measured according to ASTM D3107-Stretch, after 3 home washes). In embodiments, the elasticity in the weft direction (E_(weft)) may be the same as or higher than the elasticity in the warp direction (E_(warp)). In embodiments, the elasticity in the warp direction (E_(warp)) may be the same as or greater than the elasticity in the weft direction (E_(weft)).

In embodiments, processes disclosed may not include a step of heat setting of the fabric, i.e., the fabric of the invention may not undergo any type of heat treatment.

In embodiments, the disclosure may provide a clothing article made of or comprising an elastic woven fabric as disclosed in embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the disclosed subject matter will be set forth in any claims that are filed. The disclosed subject matter itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:

FIG. 1A and 1B displays a diagram of how a minimum warp elasticity may be determined in accordance with embodiments.

FIG. 2 displays a perspective schematic view of an exemplary embodiment of a fabric in accordance with embodiments.

FIG. 3 displays a process for producing an elastic woven fabric in accordance with embodiments.

FIG. 4 displays a process for producing an elastic woven fabric in accordance with embodiments.

FIG. 5 displays a process for producing an elastic woven fabric in accordance with embodiments.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Reference now should be made to the drawings, in which the same reference numbers are used throughout the different figures to designate the same components.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms.

These terms are only used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the present disclosure.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

The disclosure relates to a woven fabric having elastic warp yarns and elastic weft yarns. The woven fabric may be characterized in that the fabric may have an elasticity, i.e., it can be stretched, in the warp direction of the fabric, at least 25% of its original length. In embodiments, the fabric may have an elasticity of at least 30% in the warp direction. The elasticity may be measured according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, the elasticity of the fabric in the weft direction (E_(weft)) may be equal to or higher than the elasticity of the fabric in warp direction (E_(warp)). In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be equal to or greater than the elasticity of the fabric in weft direction (E_(weft)).

In view of the fact that, in embodiments, the woven fabric of the disclosure may be elastic in both the warp and weft directions, it may be defined as a “bi-stretch” woven fabric.

As used herein, the term “elastic yarn” may refer to a yarn comprising an elastomeric fiber covered by a wrap, i.e., a core-spun yarn, which may provide characteristics of elasticity to the woven fabric.

Suitable fibers for the elastic filament may include polyurethanic fibers such as, but not limited to elastane (e.g.

Lycra®, Dorlastan (a registered trademark of Asahi Kasei Spandex Europe GMBH, LLC), spandex (RadicciSpandex Co.), and lastol (Dow Chemical XLA).

Suitable fibers for the less elastic, control, filament may include, but are not limited to: polyamides such as nylon (e.g., nylon 6, nylon 6,6, nylon 6,12, and the like), polyester, polyolefins (such as polypropylene and polyethylene), mixtures and copolymers of the same, and PBT and bicomponent filaments (namely elastomultiesters such as PBT/PET and PTT/PET filaments). In embodiments, suitable staple fibers for the sheath may include, but are not limited to polyester fibers and natural fibers. In embodiments, suitable staple fibers for the sheath may include, but are not limited to cotton fibers that may have the ability to be dyed.

In embodiments, elastic yarns which may be utilized in the disclosure may thus be disclosed in WO2012/06248. In embodiments of the elastic yarns, the two filaments of the core may be twisted at a twisting number of at least 200 twists per meter. In embodiments of the elastic yarns, the two filaments of the core may be twisted at a twisting number in the range of 300 to 600 twists/meter. In embodiments, the twisting may provide the effect of the two filaments elongating and retracting as a single filament.

In embodiments, the comfort level of the bi-stretch fabric may be improved. This improvement may be obtained due to the E_(warp) being lower than the E_(weft). In this bi-stretch fabric, the warp yarns may provide a better support against the gravity and the greater E_(weft) than E_(warp) may allow a better shaping of the body.

In embodiments, an elastic woven fabric may have an elasticity in the warp direction (E_(warp)) in the range of 25% to greater than 75%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, an elastic woven fabric may have an elasticity in the warp direction (E_(warp)) in the range of 25% to 90%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, an elastic woven fabric may have an elasticity in the warp direction (E_(warp)) in the range of 30% to 90%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, an elastic woven fabric may have an elasticity in the warp direction (E_(warp)) in the range of 30% to greater than 60%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, an elastic woven fabric may have an elasticity in the weft direction (E_(weft)) in the range of 30% to over 150%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, an elastic woven fabric may have an elasticity in the weft direction (E_(weft)) in the range of 30% to 150%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes. In embodiments, an elastic woven fabric may have an elasticity in the weft direction (E_(weft)) in the range of 50% to over 140%, according to ASTM D3107 MODIFIED (Stretch) after 3 home washes.

In embodiments, the elastic woven fabric may have elasticity in the weft direction (E_(weft)) that may be twice the elasticity in the warp direction (E_(warp)). In embodiments, the E_(weft) may be two to three times E_(warp).

In embodiments, the bi-stretch fabric may provide a high elasticity in both the warp and the weft direction, an improved recoverability, and a reduction of growth.

In embodiments, improved performance may be obtained by the bi-stretch fabric due to the high elasticity that may be more than what people may need in their daily lives. In view of this, a normal daily use may not require the use of all elastic and elongation capacities of the fabric. Therefore, in embodiments, the fabric of the disclosure may not be overstretched or stressed, thus avoiding damage and lack of performance such as lack of recovery, increased growth, and bagging.

As an example, in embodiments, in the so called “super-skinny” garments, the garments' cut may be smaller than the normal body size. Therefore, just wearing super skinny garments may cause the fabric to stretch, which the garments may be made of. In view of this fact, normal use may cause overstretching of the fabric of the super-skinny garment, thus causing damage to the fabric as well as bagging at knees and elbows. In embodiments, the bi-stretch fabric of the disclosure may avoid damage, bagging, and other problems. In embodiments, these problems may be avoided due to the fact that the fabric of the disclosure may be able to move with human skin, i.e., may be able to move as human skin moves due, at least in part, to its elastic properties.

In embodiments, the elastic corespun yarn may have an English cotton count ranging from 8 Ne to 90 Ne. In embodiments, the elastic corespun yarn may have an English cotton count ranging from 10 Ne to 80 Ne. In embodiments, the elastic corespun yarn may have an English cotton count ranging from 12 Ne to 60 Ne.

In embodiments, the elastic woven fabric may have a weight in the range of 3 oz/yard² to 20 oz/yard² after wash (according to ASTM D3776). In embodiments, the elastic woven fabric may have a weight in the range of 4 oz/yard² to 15 oz/yard² after wash (according to ASTM D3776). In embodiments, the elastic woven fabric may have a weight in the range of 7 oz/yard² to 14 oz/yard² after wash (according to ASTM D3776).

In embodiments, the bi-stretch fabric may be a denim fabric.

In embodiments, an elastic woven fabric may be produced by a process 300 (FIG. 3) including determining 305 the minimum warp elasticity (E_(wrap)) required and weaving 310 warp yarns and weft yarns, wherein the woven fabric may be elastic in both the warp and the weft direction and the fabric may be made to match the minimum warp elasticity (E_(warp)).

In embodiments, the fabric may not be heat set, i.e., the fabric may not undergo a thermal treatment to set its elasticity to a pre-set value. It was surprisingly found that when the elastic yarns disclosed by reference WO2012/062480, the resulting fabric may not have to be heat-set to avoid the occurrence of problems such as curling and torqueing. In embodiments, a fabric as mentioned above may undergo a thermal treatment.

In embodiments, possible combinations of stretch values (elasticity) measured by ASTM D3107 (stretch) after three home washings may include values in the ranges of 30-75; 33-35; 53-75; 27-65; 28-50; 35-100; 40-100 40-120, wherein the elasticity is given for warp-weft.

Making reference to FIG. 1A and 1B, the minimum warp elasticity required may be determined by measuring the variation in the distance between two benchmark points “A” 30 and “B” 40 taken at two opposite ends of a joint 20, such as an elbow or a knee, for example, along the axis of the limb 10 (e.g. an arm or a leg), on the skin of the future user.

In embodiments, the limb 10 may be an arm or a leg.

In embodiments, the joint 20 may be an elbow or a knee.

For example, in order to make trousers, the determination may be carried out, in embodiments, on a knee, namely above and below a knee. On the contrary, if the purpose is to obtain a fabric to make shirts, the minimum warp elasticity required may be determined on an elbow in embodiments.

In FIG. 1A, when the limb 10 is unbent, two benchmarks “A” 30 and “B” 40 may be taken at two opposite ends of a joint 20 along the axis of the limb 10.

In embodiments, the distance between benchmark “A” 30 and benchmark “B” 40 when the limb 10 is unbent may be the value X. In embodiments, when the limb 10 is bent, as shown in FIG. 1B, the distance measured along the skin of the limb 10 between benchmark “A” 30 and benchmark “B” 40 taken at two opposite ends of a joint 20, may increase to a value Y. The percentage of the variation of distance X to distance Y may be calculated with the formula (Y−X)/X. The result obtained may indicate the minimum warp elasticity required for a fabric.

In embodiments, the minimum warp elasticity required may be at least the value calculated using formula (Y−X)/X, wherein X may be the distance between the two benchmarks “A” 30 and “B” 40 taken at two opposite ends of the joint 20 along the axis of a limb 10 when the limb 10 is unbent and Y may be the distance between the same two benchmarks when the limb 10 is bent.

In embodiments, the fabric may be woven in order to obtain an elastic woven fabric that may have an E_(warp) that may be greater than the value of (Y−X)/X. In embodiments, the fabric may be woven in order to obtain an elastic woven fabric that may have an E_(warp) that may be greater than twice the value of (Y−X)/X.

In embodiments, the warp elasticity E_(warp) of the fabric may be 20% higher than the value of (Y−X)/X. In embodiments, the warp elasticity E_(warp) of the fabric may be 30% higher than the value of (Y−X)/X. In embodiments, the warp elasticity E_(warp) of the fabric may be 40% higher than the value of (Y−X)/X.

In embodiments, the disclosure may further provide a process 400 for preparing an elastic woven fabric as disclosed above and shown in FIG. 4. In embodiments, the process may include determining 405 the minimum warp elasticity required for the fabric. In embodiments, the process may further include selecting 410 an elastic yarn and a rigid yarn to be used in at least the warp yarns. In embodiments, the process may further include weaving 415 warp yarns and weft yarns such that the woven fabric may be elastic in both the warp and the weft directions. In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be at least 30% and the elasticity of the fabric in the weft direction (E_(weft)) may be higher than the elasticity in the warp direction (E_(warp)) (ASTM D3107 MODIFIED (Stretch) after 3 home washes). In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be at least 30% and the elasticity of the fabric in the warp direction (E_(warp)) may be higher than the elasticity in the weft direction (E_(weft)) (ASTM D3107 MODIFIED (Stretch) after 3 home washes).

In embodiments, the minimum warp elasticity required for the fabric may be calculated using formula (Y−X)/X, wherein X may be the distance between two benchmarks “A” 30 and “B” 40 taken at two opposite sides of a joint 20 along the axis of a limb 10 when the limb 10 is unbent and Y may be the distance between the same two benchmarks when the limb 10 is bent.

In embodiments, the disclosure may further provide a process 500 for preparing an elastic woven fabric as disclosed above and shown in FIG. 5. In embodiments, process 500 may include providing 505 corespun warp yarns and corespun weft yarns each having a stretchable core and an inelastic fiber sheath that may cover the stretchable core. In embodiments, the stretchable cores may comprise a first elastic fiber and a second fiber, wherein the second fiber may be less elastic than the first elastic fiber.

The process may further include weaving 510 the corespun warp yarns and the corespun weft yarns to create a fabric. The process may further include finishing 515 the fabric. In embodiments, the finishing 515 may provide the fabric with an elasticity in the warp direction of at least 25% and an elasticity in the weft direction of at least 25%.

In embodiments, the finishing 515 may provide the fabric with an elasticity in the warp direction of at least 30% and an elasticity in the weft direction of at least 30%.

In embodiments, the finishing 515 may provide the fabric with an elasticity in the warp direction of at least 40% and an elasticity in the weft direction of at least 40%.

In embodiments, the first fiber and second fiber may be connected together by at least one of intermingling, twisting, and coextrusion.

In embodiments, the elasticity of the fabric in the weft direction (E_(weft)) may be greater than the elasticity of the fabric in the warp direction (E_(warp)). In embodiments, the elasticity of the fabric in the warp direction (E_(warp)) may be greater than the elasticity of the fabric in the weft direction (E_(weft)).

In embodiments, the second fiber may be selected from the group of a PBT elastomultiester, a bicomponent PTT/PET, a PTT/PBT, and a nylon.

In embodiments, the first elastic fiber may be selected from the group of a polyolefin elastomer and a polyurethane elastomer.

FIG. 2 displays a woven fabric in accordance with embodiments. The woven fabric 50 may comprise warp yarns 51 and weft yarns 52. In embodiments, a first fiber 61 and a second fiber 62 (also referred to as core fibers 63 in embodiments) may be present in the core of the warp yarns 51. In embodiments, core fibers 63, including both first fibers 61 and second fibers 62, may be present in the core of the weft yarns 52.

In embodiments, the second fibers 62 may be less elastic than the first fibers 61.

FIG. 2 displays an embodiment of the woven fabric that may be a bi-directional stretch fabric. In embodiments, the fabric may be denim.

In embodiments, the bi-stretch fabric of the disclosure may be suitable to produce clothing articles comprising at least bi-stretch fabric. For example, clothing articles that may comprise the elastic woven fabric disclosed may be leggings, pants, T-shirts, sweaters, jackets, and any other garment. In embodiments, the bi-stretch fabric of the disclosure may be suitable to produce textiles other than clothing articles.

The following table may show the advantages of a fabric as described in an embodiment of the disclosure as far as growth of the fabric is concerned.

TABLE 1 Growth for 80% Growth for 50% Growth for 20% Required elastic fabric elastic fabric elastic fabric Elasticity % (ASTM D3107) (ASTM D3107) (ASTM D3107) 10 1 1 20 1.5 3 1 30 2 4 6 40 3 5 — 50 4 7 — 60 5 — — 65 5.5 — — 70 5.8 — — 75 7.5 — — 80 10 — —

In the above table, the required elasticity may be the elasticity determined or measured as previously discussed, e.g., it may be known that the elasticity required for the fabric of a legging or skinny jeans may be 20% when the actual fabric used may have a 20% elasticity. The result may be a growth of the fabric with use and a bagging resulting at the knees. Additionally, any holding and shaping power of the fabric may be decreased with time.

If, in embodiments, for a leggings or jeans garment, the used fabric has an elasticity of 50%, the growth may be only 3 or 1.5 if a fabric having 80% elasticity is utilized.

In embodiments, if a required elasticity of a fabric is 50%, the use of a 50% elastic fabric may result in a growth of 7% of the fabric compared to a growth of 4% of the fabric if a fabric having 80% elasticity is used.

In embodiments, a garment may be customized to the final user's body structure. By measuring the required elasticity on a user's body as previously mentioned it may be possible to select a garment, in embodiments, that may have an elasticity that may properly suits a user's body and movement characteristics.

For the purposes of this disclosure, the term “inelastic fiber sheath” may refer to a sheath comprising one or more fibers that may envelop and/or cover at least a portion of a stretchable core of a yarn.

For the purposes of this disclosure, the terms “method” and “process” may be interchangeable.

In embodiments of any processes disclosed, the fabric, yarn, and/or fibers may comprise any disclosed characteristics.

In embodiments, suitable elastic core spun yarns may be those disclosed in WO2008/130563, which is hereby incorporated by reference in its entirety.

In embodiments, original polymers may be utilized. For the purposes of this disclosure, the term “original polymers” may refer to polymers that are utilized that are in their original form of when they had first been discovered. In embodiments, trademarked polymers may be utilized. It is noted that trademarked polymers may vary in characteristics from original polymers, such characteristics being, for example, molecular weight, branching, and density.

While this disclosure has been particularly shown and described with reference to preferred embodiments thereof and to the accompanying drawings, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit of this disclosure. Therefore, the scope of the disclosure is defined not by the detailed description but by the appended claims. 

1. A woven fabric comprising: elastic warp yarns; and elastic weft yarns, said elastic warp yarns and said elastic weft yarns each comprising a stretchable core and an inelastic fiber sheath covering each of said stretchable cores, the stretchable cores of said elastic warp yarns and said elastic weft yarns each comprising a first elastic fiber and a second fiber, the second fiber being less elastic than said first elastic fiber, an elasticity of the fabric in the warp direction being at least 25% and an elasticity of the fabric in weft direction being at least 25%.
 2. The fabric of claim 1, the elasticity of the fabric in the warp direction being at least 40% and the elasticity of the fabric in weft direction being at least 40%.
 3. The fabric of claim 1, said first fiber and said second fiber connected together by intermingling.
 4. The fabric of claim 1, the elasticity of the fabric in the weft direction being greater than the elasticity of the fabric in the warp direction.
 5. The fabric of claim 1, the elasticity of the fabric in the warp direction being between 30% to 90%.
 6. The fabric of claim 1, the elasticity of the fabric in the weft direction being between 35% to 125%.
 7. The fabric of claim 1, the ratio of the elasticity of the fabric in the weft direction to the elasticity of the fabric in the warp direction being in the range of 1.8/1.0 to 3.0/1.0.
 8. The fabric of claim 1, said first fiber being able to elongate at least 400% of its initial length at its breaking point, said second fiber being able to elongate at least 20% of its initial length but less than the elongation of the first fiber.
 9. The fabric of claim 3, said first fiber and said second fiber being intermingled and having a number of connecting points within the range of 50 to 200 points per meter.
 10. The fabric of claim 3, said first fiber and said second fiber being connected by twisting and having a number of twists per meter in the range of 300 to 600 twists per meter.
 11. The fabric of claim 1, said elastic warp and weft yarns comprising a corespun yarn comprising an English cotton count ranging from 10 Ne to 50 Ne.
 12. The fabric of claim 1, said fabric having a weight after washing ranging from 135 g/m² to 508 g/m².
 13. The fabric of claim 1, the fabric comprising a denim fabric.
 14. The fabric of claim 1, the fabric incorporated in a clothing article.
 15. A process of producing an elastic woven fabric, the process comprising: providing corespun warp yarns and corespun weft yarns each having a stretchable core and an inelastic fiber sheath that covers said stretchable core, said stretchable cores comprising a first elastic fiber and a second fiber, said second fiber being less elastic than said first elastic fiber; weaving said corespun warp and said weft yarns to create a fabric; and finishing said fabric, wherein the finishing provides said fabric with an elasticity in the warp direction of at least 25% and an elasticity in the weft direction of at least 25%.
 16. The process of claim 15, the finishing providing said fabric with an elasticity in the warp direction of at least 30% and an elasticity in the weft direction of at least 30%.
 17. The process of claim 15, said first fiber and said second fiber being connected together by at least one of intermingling, twisting, and coextrusion
 18. The process of claim 15, the elasticity of said fabric in the weft direction being greater than the elasticity of said fabric in the warp direction.
 19. The process of claim 15, said second fiber selected from the group of a PBT elastomultiester, a bicomponent PTT/PET, a PTT/PBT, and a nylon.
 20. The process of claim 15, said first elastic fiber selected from the group of a polyolefin elastomer and a polyurethane elastomer.
 21. The fabric of claim 1, wherein said second fiber is a bicomponent PTT/PET.
 22. The fabric of claim 1, wherein said second fiber is PET.
 23. The fabric of claim 1, wherein said first elastic fiber is a polyurethane elastomer. 